Volume 35 number 1 (2007)
Photographs of TV Cas and U Cep taken by students equipped with conventional cameras and mobile, self-made mountings are used to introduce variable stars and, in particular, eclipsing binaries. The first step-by making a simple visual comparison-is to discover that variable stars do exist. The star's brightness change is then estimated by visual comparison with surrounding stars and measured by means of digitized photographs. Plots of luminosity versus time produce a lightcurve that can be discussed in terms of the star's regularity and periodicity.